Fire suppression compositions

ABSTRACT

A fire suppression composition comprises CF 3 I and CO 2 , wherein said CF 3 I is present in an amount of from 23 mol. % to 39 mol. %, based on the total moles of CF 3 I and CO 2  present in the fire suppression composition. Alternatively, the fire suppression composition comprises CF 3 I and CO 2 , wherein said CF 3 I is present in an amount of from 53 mol. % to 85 mol. %, based on the total moles of CF 3 I and CO 2  present in the fire suppression composition.

TECHNICAL FIELD

The present disclosure relates to fire suppression compositionscomprising CF₃I and CO₂.

BACKGROUND

Halon 1301 has frequently been employed as a fire suppression agent.However, production of this agent was banned in 1994 due to its highozone depleting potential. There is therefore a desire to replace Halon1301 with more environmentally friendly fire suppression agents. Apromising alternative to Halon 1301, CF₃I (trifluoroiodomethane), faileda key MPS test, the bulk load test, and can be subject to decompositionduring use. A solution must be found that will improve the stability ofthe alternative fire suppression agents.

SUMMARY

This disclosure relates to fire suppression compositions comprisingblends of CF₃I and CO₂. The CF₃I is present in an amount of from 23 mol.% to 80 mol. %, based on the total amount of CF₃I and CO₂ present in thefire suppression composition.

In one aspect, the present disclosure provides a fire suppressioncomposition comprising CF₃I and CO₂, wherein said CF₃I is present in anamount of between 23 mol. % and 40 mol. %, e.g. from 23 mol. % to 39%,based on the total moles of CF₃I and CO₂ present in the fire suppressioncomposition.

The CF₃I may be present in an amount of from 24 mol. % to 38 mol. %,e.g. from 25 mol. % to 37 mol. %, from 26 mol. % to 36 mol. %, from 27mol. % to 35 mol. %, or from 28 mol. % to 34 mol. %, based on the totalmoles of CF₃I and CO₂ present in the fire suppression composition.

The CF₃I may present in an amount greater than 29 mol. % based on thetotal moles of CF₃I and CO₂ present in the fire suppression composition,e.g. from 29 to 39 mol. %, 29 to 38 mol. %, 30 to 37 mol. %, 31 to 36mol. %, 32 to 35 mol. %, or from 33 to 34 mol. %, based on the totalmoles of CF₃I and CO₂ present in the fire suppression composition.

The CF₃I may be present in an amount of from 23 mol. % to 39.9 mol. %,for example from 24.5 mol. % to 39.5 mol. %, from 25.5 mol. % to 39 mol.%, or from 30 mol. % to 38 mol. %, based on the total moles of CF₃I andCO₂ present in the fire suppression composition.

The CF₃I may be present in an amount of 22.5 mol. %, 23.5 mol. %, 25.3mol. %, 25.5 mol. %, 30.4 mol. %, 30.5 mol. %, 32.4 mol. %, 32.5 mol. %,35.1 mol. %, 35.5 mol. %, 39.9 mol. % or any ranges between any of thesevalues, based on the total moles of CF₃I and CO₂ present in the firesuppression composition. The CF₃I may be present in an amount of 30 to35 mol. %, based on the total moles of CF₃I and CO₂ present in the firesuppression composition.

In a further aspect of the present disclosure, there is provided a firesuppression composition comprising CF₃I and CO₂, wherein said CF₃I ispresent in an amount greater than 53 mol. %, based on the total moles ofCF₃I and CO₂ present in the fire suppression composition.

The CF₃I may be present in an amount of from 53 mol. % to 85 mol. %,e.g. 53 mol. % to 75 mol. %, based on the total moles of CF₃I and CO₂present in the fire suppression composition.

The CF₃I may be present in an amount from 53 to 84 mol. %, 54 mol. % to80 mol. %, 55 mol. % to 79 mol. %, 56 to 78 mol. %, 58 to 76 mol. %, 59to 75 mol. %, 60 to 72 mol. %, 62 to 70 mol. %, 63 to 69 mol. %, 64 to68 mol. %, or 65 to 67 mol. %, based on the total moles of CF₃I and CO₂present in the fire suppression composition.

The CF₃I may be present in an amount of 67.2, 67.5, 75.5, 75.7, 80.1,80.5, 83.3, 83.5 mol. % or any ranges between any of these values, basedon the total moles of CF₃I and CO₂ present in the fire suppressioncomposition. The CF₃I may be present in an amount of 67 to 80 mol. %,based on the total moles of CF₃I and CO₂ present in the fire suppressioncomposition.

The amount of CF₃I, expressed as a percentage of the total amount ofCF₃I and CO₂ in the fire suppression composition, may also be expressedin weight %.

Thus, in a further aspect of the present disclosure, there is provided afire suppression composition comprising CF₃I and CO₂, wherein said CF₃Iis present in an amount of between 57 weight % and 75 weight %, e.g.from 57 weight % to 74 weight %, based on the total weight of CF₃I andCO₂ present in the fire suppression composition.

The CF₃I may be present in an amount of from 57 weight % to 74 weight %,for example from 58 to 73 weight %, from 60 to 72 weight %, from 61 to71 weight %, from 62 to 70 weight %, or from 63 to 69 weight %, based onthe total weight of CF₃I and CO₂ present in the fire suppressioncomposition.

The CF₃I may be present in an amount of greater than 65 weight %, e.g.65 to 74 weight %, from 65 to 73 weight %, 66 to 72 weight %, 67 to 71weight %, from 68 to 70 weight %, or from 69 to 70 weight %, based onthe total weight of CF₃I and CO₂ present in the fire suppressioncomposition.

The CF₃I may be present in an amount of from 57 weight % to 74.7 weight%, for example from 59 weight % to 74.4 weight %, from 60.3 weight % to74 weight %, or from 65 weight % to 73 weight %, based on the totalweight of CF₃I and CO₂ present in the fire suppression composition.

The CF₃I may be present in an amount of 56.4 weight %, 57.8 weight %,60.1 weight %, 60.3 weight %, 66 weight %, 66.1 weight %, 68.1 weight %,68.2 weight %, 70.7 weight %, 71 weight %, 74.7 weight % or any rangesbetween any of these values, based on the total weight of CF₃I and CO₂present in the fire suppression composition.

In a further aspect of the present disclosure, there is provided a firesuppression composition comprising CF₃I and CO₂, wherein the CF₃I ispresent in an amount of greater than 83 weight %, for example from 83weight % to 96 weight %, e.g. 83 weight % to 93 weight %, based on thetotal weight of CF₃I and CO₂ present in the fire suppressioncomposition.

The CF₃I may be present in an amount of from 83 to 96 weight %, 84weight % to 95 weight %, 84 weight % to 94 weight %, 85 weight % to 94weight %, 86 to 93 weight %, 87 to 92 weight %, 87 to 91 weight %, 87 to90 weight %, 88 to 90 weight %, 89 to 90 weight %, or 90 to 91 weight %based on the total weight of CF₃I and CO₂ present in the firesuppression composition.

In one aspect of the disclosed compositions, CF₃I is present in anamount of 90.1, 90.2, 93.2, 93.3, 94.7, 94.8, 95.7, 95.7 weight %, orany ranges between any of these values, based on the total weight ofCF₃I and CO₂ present in the fire suppression composition.

As the amount of CF₃I is expressed as proportion of the total of CF₃Iand CO₂, it will be understood that the percentage of CO₂ (alsoexpressed as a proportion of the total) is the remainder of this total(i.e. 100 minus the percentage of CF₃I). Where the composition consistsof, or consists essentially of, CF₃I and CO₂, these proportions willalso be applicable to the composition as a whole. Fire suppressioncompositions comprising such blends of CF₃I and CO₂, e.g. those withmolar ratios of CF₃I to CO₂ of from 3:7 to 7:13, or 2:1 to 5:1 formafurther aspect of this disclosure.

In addition to CF₃I and CO₂, the fire suppression composition asdisclosed herein can further comprise one or more additional components.The additional components may be selected from a gas (e.g. an inertgas), an additional fire suppressant compound, odorants, or combinationsthereof.

The total amount of additional components, if present, may be present inan amount of up to 20 weight %, based on the total weight of the firesuppression composition.

The total amount of additional components present in the firesuppression composition may be up to 18 weight %, up to 15 weight %, upto 10 weight %, up to 8 weight %, up to 5 weight % or up to 3 weight %,(e.g. from 0.1 weight % up to these limits) based on the total weight ofthe fire suppression composition. In some aspects, the total amount ofadditional components present in the fire suppression composition may beup to 2 weight % or up to 1 weight %, e.g. 0.1 weight % to 2 weight % or0.1 weight % to 1 weight %.

The additional components, if present, may be one or more gases, e.g. aninert gas, or a propellant. Examples of suitable gases include nitrogen,argon, helium and neon, and combinations thereof.

The optional gas may be present in an amount of up to 1 weight %, basedon the total weight of the fire suppression composition. For example,the gas may be present in an amount of up to 0.9 weight %, up to 0.8weight %, up to 0.7 weight %, up to 0.6 weight %, up to 0.5 weight %, upto 0.4 weight %, up to 0.3 weight %, up to 0.2 weight % or up to 0.1weight %, based on the total weight of the fire suppression composition.If present, a lower limit for the gas may be 0.05 weight %.

The additional component, if present, may be an additional firesuppressant compound, i.e. one that is not CF₃I or CO₂.

The additional fire suppressant compound, if present, may be present inan amount of up to 20 weight %, based on the total weight of the firesuppression composition. For example, the total amount of additionalfire suppressant compound present in the fire suppression compositionmay be up to 18 weight %, up to 15 weight %, up to 10 weight %, up to 8weight %, up to 5 weight % or up to 3 weight % based on the total weightof the fire suppression composition. If present, a lower limit for theadditional suppressant may be 0.1 weight %.

The additional component, if present, can be an odorant. Examples ofodorants include compounds which include one or more carbon-carbondouble bonds, and/or compounds which are aromatic. The odorant compoundsmay further include a hydroxyl group, an iodine group, or both.

The odorant compound, if present, may be present in an amount of up to 1weight % based on the total weight of the fire suppression composition.For example, the odorant may be present in an amount of up to 0.9 weight%, up to 0.8 weight %, up to 0.7 weight %, up to 0.6 weight %, up to 0.5weight %, up to 0.4 weight %, up to 0.3 weight %, up to 0.2 weight % orup to 0.1 weight %, based on the total weight of the fire suppressioncomposition. If present, a lower limit for the odorant may be 0.05weight %.

The present disclosure also provides a device, e.g. a fire extinguisher,fire suppression device, or storage device, comprising a firesuppression composition as herein described.

Also disclosed is a device, e.g. a fire extinguisher, fire suppressiondevice, or storage device, comprising at least two separate containers,wherein the first container comprises CF₃I and the second containercomprises CO₂. The proportions of the CF₃I and the CO₂ are as describedherein. The contents of the containers can be combined immediately priorto use to produce a fire suppression composition as herein described. Aswould be understood, the first and/or second container can comprise oneor more additional components (e.g. one or more additional components asherein described) or any additional components can be stored in afurther container or containers.

Disclosed is a fire suppression system or device comprising a firesuppression composition as herein described, or the components thereof.The fire suppression system can comprise a fire suppression compositionherein described and a dispensing component (such as one or more nozzlesthat disperse the fire suppression composition). In an alternativeaspect, the fire suppression system can contain: (i) two separatecontainers, wherein the first container comprises CF₃I and the secondcontainer comprises CO₂, and (ii) a combining and dispensing componentwhich is configured to combine the contents of the separate containersto form a fire suppression composition as herein described, and thendispense said resulting fire suppression composition.

Also disclosed is a method for extinguishing a fire comprising using afire suppression composition as herein described.

Disclosed is a method for preparing a fire suppression composition asherein described, said method comprising combining CF₃I and CO₂ suchthat CF₃I is present in an amount as herein described in relation to thetotal amount of CF₃I and CO₂. The method may comprise the steps of (i)providing CF₃I, (ii) providing CO₂ and (iii) combining CF₃I and CO₂ suchthat CF₃I is present in an amount as herein described in relation to thetotal amount of CF₃I and CO₂. The method can further comprise theadditional step of adding one or more additional components as hereindescribed.

In some aspects, the fire suppression composition of the presentdisclosure consists of, or consists essentially of, CF₃I and CO₂ in theproportions described herein.

DETAILED DESCRIPTION

CF₃I is an environmentally friendly alternative to fire suppressionagents like Halon 1301 because CF₃I has a lower ozone depletionpotential. The lower ozone depletion potential is due to the lowerstability of the molecule. However, the lower stability (or theincreased tendency to degrade) presents a challenge for storage and useof CF₃I or blends containing CF₃I as a fire suppression agent. The lowerstability has discouraged the use of CF₃I in fire suppressionapplications as it can decompose, thus reducing its efficacy. Thepresent disclosure involves addition of CO₂ to the CF₃I, which has beenfound to improve stability of CF₃I.

When released, the CO₂ is able to remove a large amount of heat from itssurroundings (i.e. has a high latent heat of vaporization). Thistemperature reduction can reduce the severity of the fire, as well asreducing the decomposition rate of CF₃I, maximizing the available CF₃Ipresent when the fire suppression composition is used to extinguish afire.

The presence of CO₂ in the fire suppression composition can reduce thetemperature of the atmosphere in the space to be protected to below 370°C. (700° F.), e.g. to below 360° C., to below 350° C., to below 340° C.,to below 330° C., to below 320° C., or to below 315° C. (600° F.).

CO₂ is a physically acting fire suppression agent and CF₃I is achemically acting agent. Combining these two different types of agent asdescribed herein results in a synergistic combination. Morespecifically, the blends of CO₂ and CF₃I as disclosed herein have beenshown to be a synergistic combination. The combination of these twocomponents has surprisingly resulted in a fractional inertingcomposition number of less than the sum of the two components whenmeasured separately. The effect of this is that the combination of thesetwo components has an enhanced ability to extinguish a fire than the twocomponents would have had if used separately in the same amount.

It has also been found that fire suppression compositions according tothe present disclosure can have a reduced vapor pressure, and in someinstances, a vapor pressure in the same range as that of conventionalfire suppression agents such as Halon 1301. The reduced vapor pressureallows the fire suppression composition to be used in conventionalhardware such as preexisting fire extinguishing containers and devices.

The present disclosure will now be further described by way of thefollowing non-limiting examples.

EXAMPLES

Testing Procedure

Testing was carried out against propane-air explosions in a 42 L sphere.The most explosive propane-air mixture is 4% propane in air. Thisconcentration was therefore used to assess the relative performance ofextinguishing agents and blends thereof.

The sphere was evacuated. Whilst monitoring the pressure transducer,propane was added to a pressure of 0.04 atm (4% in the final mix). Theagent or agents were added at the desired concentration. Air was thenadded to raise the pressure in the sphere to 1.00 atm. A fan can then beused to ensure that all the gases are mixed homogeneously throughout thesphere. A spark was ignited using a center point spark ignition and thepressure rise was monitored by a data logger. A pressure rise of 1 psior lower is designated as a pass.

The standards used for inerting testing are:

ASTM E2079-07—the standard test method for limiting oxidantconcentration in gases and vapors

BS EN 1839:2012—determination of explosion limits in gases and vapors

BS EN 15967:2012—determination of maximum explosion pressure and themaximum rate of pressure rise of gases and vapors.

Fractional Inerting Contribution

When assessing blends of components, the concept of fractional inertingcontribution is used. This is defined as:

${FIC} = {\sum\limits_{i = 1}^{n}\frac{C_{i}}{{IC}_{i}}}$Where C_(i) is the concentration of component iAnd IC_(i) is the inerting concentration of component i.Thus, inerting should be attained when FIC=1 (i.e. the sum of individualconcentrations has reached the overall required amount to achieveinerting). It therefore follows that if inerting is achieved at FIC lessthan 1, then the blend is more effective than the sum of its components.In other words, the blend is exhibiting synergy.Blends of CF₃I and CO₂

Blends of CF₃I and CO₂ were evaluated and it was found that successfulinerting results were found at FIC values of lower than 1:

TABLE I Rel. wt to Rel. vol Pres 6% to 6% Mol. Propane CF₃I CO₂ Mol riseHalon Halon % Example (Vol %) (Vol %) (Vol %) Ratio (psig) FIC 1301 1301CF₃I* 1 3.98 2.93 8.64 1:3 0.99 0.76 1.04 1.36 25.3 2 4.01 3.24 7.42 3:70.91 0.76 1.04 1.27 30.4 3 4.02 3.31 6.92 6:13 0.78 0.76 1.03 1.22 32.44 4.05 3.49 6.46 7:13 0.9 0.77 1.04 1.2 35.1 *Mol. % CF₃I expressed as aproportion of the moles of CF₃I and CO₂

TABLE II Rel. wt to Rel. vol Pres 6% to 6% Mol. Propane CF₃I CO₂ Molrise Halon Halon % Example (Vol %) (Vol %) (Vol %) Ratio (psig) FIC 13011301 CF₃I* 5 4.04 5.19 2.53 2:1 0.94 0.89 1.22 1.06 67.2 6 3.98 5.471.76 3:1 0.97 0.90 1.25 1.03 75.7 7 4.08 6.01 1.49 4:1 0.97 0.98 1.361.09 80.1 8 4.01 6.49 1.3 5:1 0.96 1.04 1.46 1.15 83.3 *Mol. % CF₃Iexpressed as a proportion of the moles of CF₃I and CO₂

As can be seen from Tables I and II above, all examples show asynergistic effect between the CF₃I and CO₂ in the blend. Examples 1˜4show a particularly good synergistic effect, coupled with an acceptablevapor pressure/temperature characteristics. Examples 5-8 show asynergistic effect, and these examples have improved vaporpressure/temperature characteristics.

References to “comprises” and/or “comprising,” should be understood toalso encompass “consist(s) of”, “consisting of”, “consist(s) essentiallyof” and “consisting essentially of”.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the presentdisclosure. As used herein, the singular forms “a”, “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,element components, and/or groups thereof.

While the present disclosure has been described with reference to anexemplary embodiment or embodiments, it will be understood by thoseskilled in the art that various changes may be made and equivalents maybe substituted for elements thereof without departing from the scope ofthe present disclosure. In addition, many modifications may be made toadapt a particular situation or material to the teachings of the presentdisclosure without departing from the essential scope thereof.Therefore, it is intended that the present disclosure not be limited tothe particular embodiment disclosed as the best mode contemplated forcarrying out this present disclosure, but that the present disclosurewill include all embodiments falling within the scope of the claims.

The invention claimed is:
 1. A fire suppression composition comprisingCF₃I and CO₂, wherein said CF₃I is present in an amount of from 23 mol.% to 39 mol. %, based on the total moles of CF₃I and CO₂ present in thefire suppression composition; wherein a total amount of additionalcomponents present in the fire suppression composition is in an amountof up to 20 weight %, based on the total weight of the fire suppressioncomposition.
 2. The fire suppression composition according to claim 1,wherein said CF₃I is present in an amount of from 29 mol. % to 39 mol.%, based on the total moles of CF₃I and CO₂ present in the firesuppression composition.
 3. The fire suppression composition accordingto claim 1, wherein said CF₃I is present in an amount of from 30 mol. %to 35 mol. %, based on the total moles of CF₃I and CO₂ present in thefire suppression composition.
 4. The fire suppression compositionaccording to claim 1, wherein the additional components are selectedfrom one or more gases, additional fire suppressant compounds, odorants,or combinations thereof.
 5. The fire suppression composition accordingto claim 1, wherein the total amount of additional components arepresent in an amount of up to 5 weight %, based on the total weight ofthe fire suppression composition.
 6. A fire suppression system or devicecontaining the fire suppression composition as claimed in claim
 1. 7. Afire suppression system or device according to claim 6, wherein saidfire suppression system additionally comprises a dispensing component.8. A method for preparing a fire suppression composition as claimed inclaim 1, said method comprising the steps of (i) providing CF₃I, (ii)providing CO₂ and (iii) combining CF₃I and CO₂ to form a firesuppression composition as defined in claim
 1. 9. A method for preparinga fire suppression composition as claimed in claim 1, said methodcomprising the steps of (i) providing CF₃I, (ii) providing CO₂ and (iii)combining CF₃I and CO₂ to form a fire suppression composition as definedin claim 1.